The Foundation for Information Policy Research (FIPR), a leading advisory group on internet issues, has written to the Information Commissioner arguing that Phorm's ad targeting system is illegal.
In an open letter posted to the think tank's website today, the group echoes concerns voiced by London School of Economics professor Peter Sommer that Phorm's planned partnerships with BT, Virgin Media and Carphone Warehouse are illegal und the Regulation of Investigatory Powers Act 2000 (RIPA).
The letter, signed by FIPR's top lawyer Nicholas Bohm, states: "The explicit consent of a properly-informed user is necessary but not sufficient to make interception lawful.
"The consent of those who host the web pages visited by a user is also required, since they communicate their pages to the user, as is the consent of those who send email to the user, since those who host web-based email services have no authority to consent to interception on their users' behalf."
Phorm claims that all sensitve data will not be profiled, but FIPR argues its "restricted sites" blacklist system will be ineffective because of the vast array of webmail and social networking sites web users now visit.
Bohm uses the letter to urge the Information Commissioner, Richard Thomas, to ignore the conclusions of the Home Office, which advised BT and the other ISPs that Phorm's technology is legal. Thomas' office first said it planned to look into Phorm on 29 February. It told El Reg it only learned of the ISPs' data pimping plans two days before they were publicly announced on 14 February.
Earlier today web inventor Sir Tim Berners-Lee said he would personally not want his traffic to be profiled by Phorm, and called on BT, Virgin Media and Carphone Warehouse to make the "service" opt-in only. ®